托福阅读机经背景材料：牙齿健康

　　How Medical technology is paving the way for people to (1)throw out those dentures, bridges((假牙上的)齿桥) or synthetic implants, and grow their own teeth back. I’m talking genuine teeth, the real McCoy. And you grow them in your mouth, in the very gaps where your dear departed teeth used to sit. The magic dust, if you will, are stem cells that come from your own gums.

　　Stem cells are basically uNPRogrammed cells. They’re useful because they can be programmed to (2)take on various functions, depending on what a body’s in need of.You got it.So in this case, stem cells in your gums would be extracted in order to be programmed in a lab to grow a tooth. Then doctors would insert them back into your gums, so they can do their job.

　　The procedure will be a lot less invasive and less traumatic than many current tooth replacement options. It’s beneficial too because a living tooth isn’t motionless, but adjusts in response to a person’s bite, and in doing so it can help maintain the health of the surrounding teeth and gums.

　　Will the technology be available any time soon?Not but i'm planning on losing any teeth of course.I mean so I can tell my friend Bob.

　　Tell Bob the Scientists anticipate making the procedure available to the public in about five years.

　　Notes:

　　(1)throw out ['θr?uaut] v.扔掉;伸出;说出;否决;突出

　　Never throw out anybody .

　　不要放弃任何人。

　　(2)take on 承担;呈现;具有;流行;接纳;雇用;穿上

　　The old term has taken on a new meaning.

　　这个旧词有了新的含义。